In article . com, " wrote:
How much plant biomass is needed per human?
[snip]
Asked another way:
Assume that one normal healthy adult human is placed in a sealed
environment with everything needed, except a renewable oxygen supply,
and he wants to live there indefinitely. How much plant life should
be included in this environment?

Perhaps it will depend on how big the "environment" is? If too small,
and too much plant life, the poor bugger might die of suffocation
before dawn if the door is shut at sunset!

(Ignore the fact that the artificial environment will almost certainly
degrade quickly due to other causes.)

Cheers, Phred.

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LID